漢魏洛陽城穀水水文考

Abstract

In examining the environments that sustain cities as large-scale settlements, there is no questioning the fact that the water environment is an essential issue. This article deals with the extraordinary city of Luoyang during the Han-Wei period, and in examining its geographic location and the character of its river water in terms of quality and quantity, the existence of the Gushui 穀水 River, the third river of the Luoyang Basin, is recognized as the most important element of the water environment in sustaining the city. In this article, I publish the results of local surveys conducted intermittently while I was in Luoyang, as well as a reconstruction of the Gushui waterways based on the reports of new excavations and the locations of systemic water-related archaeological sites and argue the place of the Gushui in the context of the environment sustaining the city. The mere mention of Luoyang brings to mind the geography of the city governed by the Luoshui 洛水 River. However, the difference in relative elevations of the base of Mt. Mangshan 邙山 and the river's course is great, and thus there were many difficulties in making use of the Luoshui. People thus sought to use the Gushui (the modern-day Jianhe 澗河 River). However, it was the Yangqu 陽渠 Channel that was the irrigation channel that drew water from the Gushui. I had previously proposed the location of the Yangqu Channel on the basis of my topographical survey, and with the successive publication of the results of archaeological surveys, my view has been confirmed as of 2011. While making reference to the latest archaeological findings, this article considers the various problems of the Gushui water system, such as the condition of the old course of the Gushui, the method of using the Yangqu Channel to transport water, the location of the Qianjin Barrage 千金堨 the water circulation problem of Luoyang Castle, the role of the moat of the Biyong 辟雍 imperial ceremonial site, and the existence of two waterways, the northern and southern, within the eastern district of the Yangqu. Additionally, in considering the culture of Luoyang in the Wei-Jin period, the problem of the site of the Qingu valley 金谷 which was the location of the activities of the Twenty-Four Comrades of Qingu 金谷二十四友 also arises. Given the fact that the gullies below the Fenghuangdi 鳳凰臺 tableland in Mengjin 孟津 Prefecture were unsuitable for human habitation according to the Shuijingzhu 水經注, this area is inappropriate. On the other hand, there is no record of the Qinshuihe 金水河 River, which corresponds to the Chanshui 瀍水 River on the western edge of the Luoyang Basin, in the Shuijingzhu. Using evidence from other written sources such as epitaphs, I have discovered a misordered portion in the text of the Shuijingzhu. The Qingushui 金谷水 River is in fact the Qinshuihe, and as it was precisely a river valley blessed with an excellent water environment, it was also a place where nobles of the Wei and Jin would go into reclusion. This precise information on the Gushui above is likely to become a basic, indispensable source for the study of Luoyang during the Han-Wei period. Exploring the water environment that is essential to the human living environment, we can glimpse an aspect of the environment required to sustain the large-scale settlement (city) that was Luoyang in the Han-Wei period.